I used this last time to get some numbers.
CrystalDiskMark – hard disk benchmark software
Treat it like a dyno, use the same program on the computer with an issue and one of the ones that's working as expected.
If the numbers are in the same ballpark, it could be CPU or software or something else. If it's way slower, I'd suspect BIOS settings, some weird file system problem from the cloning, or a driver problem of some sort.
Also, if it's not too hard to swap back and forth, you could even try the benchmark on the new drive vs. old drive to see the performance difference on the same hardware.
Just redownloaded it and ran it as a reference point. This is an Intel x25-m in a 3-4 year old Dell D630.
